Bugtraq mailing list archives
Re: HP-UX setprivgrp()
From: Valdis.Kletnieks () vt edu (Valdis.Kletnieks () vt edu)
Date: Fri, 8 Nov 1996 15:02:07 -0500
--==_Exmh_167594504P Content-Type: text/plain; charset=us-ascii On Thu, 07 Nov 1996 22:51:54 +0100, you said:
Maybe a race condition can be won between the times the setuid bits are changed by chown().Don't bother trying, system calls are atomic... but you can use this
Have you in fact verified that this is guaranteed true on a multiprocessor system? Remember that the other side(s) of the machine can still be running, and the kernel needs to explicitly lock out any activity that it doesn't want to be seen. Doing this in an efficient manner is in fact the single hardest thing with building a good MP system - you have to minimize the locked sections of code so the other CPUs can proceed as often as possible. I haven't checked a Unix kernel, but IBM's VM operating system has on the order of 200 or so different locks to provide as fine granularity as needed. Of course, sometimes the lock turns out to be a bit TOO granular.. ;) -- Valdis Kletnieks Computer Systems Engineer Virginia Tech --==_Exmh_167594504P Content-Type: application/pgp-signature -----BEGIN PGP MESSAGE----- Version: 2.6.2 iQCVAwUBMoORvdQBOOoptg9JAQE5LgP+OctSqK5A1TmqAXhLco7a7JAdin4xjeVW +Wka+sMx9y9w2sTGxIg/8yy7uFPR55aJxfL4grmTBMb3OIcUvsIbxLEGxqqqjwgP RYVKS13I8jx2woG9p2CN2g7408UioJ+IhaiXP5qURyjCQDKDLzMvQEj7+BUtQtsY Bt6kA5PtTIU= =RsNP -----END PGP MESSAGE----- --==_Exmh_167594504P--
Current thread:
- HP-UX setprivgrp() Eduardo E. Silva (Nov 07)
- <Possible follow-ups>
- Re: HP-UX setprivgrp() Dominique Quatravaux (Nov 07)
- Re: HP-UX setprivgrp() Valdis.Kletnieks () vt edu (Nov 08)
- Bos: Firewall-1 ping bug...? Eduardo E. Silva (Nov 08)
- Re: HP-UX setprivgrp() dsiebert () icaen uiowa edu (Nov 08)
- Syslogd and Solaris 2.4 Denis Campeau (Nov 08)
- Syslogd and Solaris 2.4 Scriptors of DOOM (Nov 09)
- CIAC Bulletin H-03: HP-UX suid Vulnerabilities Bill Orvis (Nov 09)
- CIAC Bulletin F-04: HP-UX Ping Vulnerability Bill Orvis (Nov 09)
- Re: HP-UX setprivgrp() Valdis.Kletnieks () vt edu (Nov 08)